2-imino-4-thiazolidones and preparation



United S 2-IMINO-4-THIAZOLIDONES AND PREPARATION George W. Sawdey, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey 3 Claims. (Cl. 260-240) This invention relates to new products and new photographic elements protected against the harmful effects of ultraviolet radiation.

This application is a division of my application Serial No. 419,239, filed March 29, 1954, now U. S. Patent 2,739,888, issued March 27, 1956.

It is known that certain materials such as cellulosic films and photographic layers, are adversely affected by ultraviolet radiation when such materials are exposed to daylight. In the case of photographic layers, the ultraviolet radiation sometimes causes undesired exposure of the layer, or layers, since photographic silver halide emulsions are sensitive to blue, violet and ultraviolet regions of the spectrum, in addition to any other sensi tivity which may be given them, and in the exposure of such material, it is frequently desirable to prevent the action of ultraviolet light on the sensitive emulsion. This is especially true in the case of photographic materials designed for use in color photography where the film has been sensitized to the longer wavelength regions where it is desirable to record only the rays of the visible spectrum.

Color photographs on multilayer photographic material, particularly where the dye images are formed in sensitive emulsion layers by color development, are susceptible to fading and discoloration by the action of ultraviolet radiation to which the photographs are subjected during viewing. It is also known that the residual couplers contained in the emulsion layers after formation of the picture images in certain processes are attacked by ultraviolet radiation and form a stain which is undesirable in the finished photograph. The action of ultraviolet radiation on finished color photographs is particularly noticeable in positive prints on paper or other opaque supports, since this type of print is frequently viewed in daylight where there is a high content of ultraviolet radiation. This dye fading and yellowing appears to be caused primarily by those wavelengths of light which lie close to the visual region of the spectrum, i. e. 360400 millimicrons.

I have now found that certain new ultraviolet absorbing compounds can be used to overcome the aforementioned difliculties, Without attendant harmful action by the ultraviolet absorbing compound itself.

It is, therefore, an object of my invention to provide new compounds and photographic elements protected against the harmful effects of ultraviolet radiation. A further object is to provide photographic color materials which have been protected against the harmful effects of ultraviolet radiation. Other objects will become apparent from a consideration of the following description.

The ultraviolet absorbing compounds which I propose to employ in my invention are advantageously repre sented by the following general formula:

meson a mesa/240 SS1REEEREniE-lm L SEARCH tented July 2, 1957 wherein R represents a hydrogen atom, an alkyl group (e. g. methyl, ethyl, fl-hydroxyethyl, ,B-sulfoethyl, p-diethoxyethyL propyl, isopropyl, butyl, isobutyl, amyl, hexyl, heptyl, octyl, nonyl, decyl, lauryl, cetyl, etc.), a cycloalkyl group (e. g. cyclopentyl, cyclohexyl, etc.), an aryl group [e. g. phenyl, 0-, m-, and p-tolyl, o-, m-, and p-ethylphenyl, p-isopropylphenyl, p-amylphenyl, o-, m-, and p-methoxyphenyl, o-, m-, and p-ethoxyphenyl, B-hydroxyethylphenyl, o-, m-, and p-chlorophenyl, o, m-, and p-hydroxyphenyl, o-, m-, and p-sulfophenyl and alkali metal salts thereof, (e. g. sodium, potassium, etc), 4-methoxy-3-sulfophenyl (and alkali metal salts thereof, e. g. sodium, potassium, etc.), 2,4-dicarboxymethoxyphenyl (and alkali metal salts thereof, e. g. sodium, potassium, etc.), o-, m-, and p-carboxyphenyl (and alkali metal salts thereof, e. g. sodium, potassium, etc.),

. 3-(3-sulfobenzamido)phenyl (and alkali metal salts thereof, e. g. sodium, potassium, etc.), o-carbobutoxyphenyl, diamylphenoxyacetoxyphenyl, etc., or an aralkyl group (e. g. benzyl, ,B-phenylethyl, a-phenylethyl, etc], R1 represents an aryl group (e. g. those aryl groups defined above wherein R is an aryl group), and Q represents a divalent, non-metallic atom (e. g. oxygen, sulfur, etc.) or irnino radical (e. g. irnino, phenylimino, o-, m-, and p-chlorophenylimino, benzylimino, ,B-phenylethylimino, u-phenylethylimino, o-, m-, and p-toluimino, o-, m-, and p-ethylphenylimino, p-amylphenylimino, o-, m-, and pethoxyphenylimino, etc.)

These ultraviolet psgrbing compounds can be incorporated in'Hi'iaTidtograpliiFiment in a variety of ways, depending on the ultimate use of the photographic element and the degree of protection desired. Advantageously, the ultraviolet absorbing compound can be dissolved or dispersed in a solvent medium together with a colloidal binder, such as gelatin, cellulose esters (e. g. cellulose acetate, etc.), synthetic resins (e. g. polyvinyl acetals, hydrolyzed polyvinyl acetate, etc.), etc., and the resulting mixture coated over the light-sensitive layer of the photographic element. Where the photographic element is a material intended for use in color photography, the gllrauinletjlter layer need not be an outer layer, but this layer can be placed over one of the layers subject to the harmful effects of ultraviolet radiation. For example, in a multilayer material comprising three differentially sensitized layers, the red sensitive layer being adjacent to the support, the green sensitive layer being superposed on the red sensitive layer, and the blue sensitive layer being outermost with respect to the other light-sensitive layers, the ultraviolet filter layer can be placed between the blue and green sensitive layers.

Alternatively, the ultraviolet filter layer gagvbeiplaced ween thegreen and the redsensitive layers. If desired, tlie'fiiaterial useful in absorbing the ultraviolet radiation can be incorporated directly in the light-sensitive emulsion instead of, or in addition to, being present in another layer. The amount of ultraviolet absorbing compound used can be varied, depending upon the effect desired and the use to which the material is to be put.

The water-soluble compounds of Formula I above (e. g. those containing alkali metal salts of carboxyphenyl, sulfophenyl, etc. groups) can be incorporated into the photographic element by simply bathing the element in an aqueous solution containing the ultraviolet absorbing compound. Where the outer layer contains gelatin, the ultraviolet absorbing compound becomes adsorbed to this layer. By incorporating a resinous mordant, e. g. polyvinyl pyridine methyl p-toluenesulfonate, phenolformaldehyde ion exchange resins, etc. in the outer gelatin layer (or an intermediate layer where desired), the

absorbing compounds. Thus, the ultraviolet absorbing compounds can be incorporated into the photographic element before or after (i. e. during processing) exposure. The support of the photographic element can be transparent, such as a cellulose ester (e. g. cellulose acetate, etc.) support, or the support can be opaque, such as a paper support. Other supports, such as glass, metal, etc. can be employed, if desired.

The compounds represented by Formula I above can advantageously be prepared by condensing a compound selected from those represented by the following general formula:

wherein R and Q have the values given above, together with an aldehyde of the following general formula:

Bri -H wherein R1 has the values given above. Heat accelerates the condensations, temperatures varying from room temperature to the reflux temperature being useful. An inert diluent, e. g. acetic acid, methanol, ethanol, etc. can be used, if desired. Condensing agents, such as piperidine, acetic anhydride, alkali metal carboxylates (e. g. sodium acetate, potassium acetate, etc.), etc. can be employed, if desired.

The compounds of Formula I wherein R1 contains a sulfo or carboxyl group (or alkali metal salts thereof, e. g. sodium, potassium, etc.) are new compounds and are especially useful in the bathing treatment mentioned above. They are useful in the process described in Edgerton and Stand application Serial No. 318,096, filed October 31, 1952, now U. S. Patent 2,747,996, issued May 29, 1956, being useful either in a layer of the photographic element, or in the bathing solutions disclosed therein. The compounds of Formula I can also be added to the photographic silver halide emulsion, though usually less advantageously than when employed in a separate filter layer.

The following examples will serve to illustrate the manner whereby the compounds of Formula I can be prepared.

Example 1 .-3-phenyl-Z-phenylimino-S a-sulfobenzal) -4- thiazolidone (sodium salt) SOaNa A mixture of 2.86 g. (0.01 mole) of 3-phenyl-2-phenylimino-4-thiazolidone and 2.5 g. (0.0125 mole) of o-sulfobenzaldehyde sodium salt in 50 ml. of absolute methanol containing 2 ml. of piperidine was refluxed for 2 hours. The crude product was collected by suction filtration, washed thoroughly with boiling acetone and recrystallized from boiling water.

The desired product separated on cooling in the form of pale yellowish platelets melting above 300 C. The

Example 2.5-(4-methoxy-3-sulfobenzal) 3 phenyl-Z- phenylimino-4-thiazolidone (sodium salt) OOHa S Os a A mixture of 6.7 g. (0.025 mole) of 3-phenyl-2-phenylimino-4-thiazo1idone and 5.5 g. (0.025 mole) of 4-methoxy-3-sulfobenzaldehyde sodium salt in 50 ml. of acetic acid and 5 ml. of acetic anhydride was refluxed under a water-cooled condenser for 8 hours. The cooled reaction mixture was poured into 400 ml. of water, and the solution heated on the steam bath to 90 C. The insoluble material was removed by filtration and the filtrate cooled. The solid formed was filtered and washed with 2-25 ml. portions of ice water and crystallized from boiling water. The product was a slightly tan powder, which gave the following analytical results:

Calculated for Found cza irNzosszNfl Percent Percent Example 3.5 [2,4 bis(carboxymethoxy)benzal] 3- phenyl-Z-phenylimin0-4-thiazolidone (sodium salt) OOHnCOONa CoHsN-C=O CeH5N=C C=CH OCHzCOONa Calculated for Found 02BH24N207S Prcent Perce Carbon 63.0 63. 3 Hydrogen- 4. 5 4. 6 N ltrogen 5. 3 5. 4 Sulfur 6. 0 5. 9

The dimethyl ester thus obtained was suspended in an alcoholic alkali (sodium hydroxide) solution, and the mixture shaken for several minutes. The dimethyl ester was completely hydrolyzed to the above formulated salt. This solution was then used directly for bathing film strips containing a photographic silver halide layer and a gelatin outercoat.

Example 4.3-phenyl-2-phenylimino-S-[3-(3-sulf0benzamido)benzal]-4-thiaz0lid0ne (sodium salt) A mixture of 5 g. (0.0135 mole) of 5-(3-aminobenzal)- 3-phenyl-2phenylimino-4-thiazolidone and 3.2 g. (0.0135 mole) of m-chlorosulfonylbenzoyl chloride in ml. of dry dioxane was refluxed for 3 hours. The cooled reaction mixture was poured into 500 ml. of cold water containing 3 g. of sodium aceate and the mixture stirred until the oil first formed solidified. The solid was filtered, washed with cold water, and dried. Crystallization from 5 acetonitrile gave a light tan powder which decomposed above 175 C. with the evolution of hydrochloric acid gas. The chlorosulfonyl compound thus produced had the following analysis:

Calculated for O2BH20C1N304S (541) Part:

The 5 [3 (3 chlorosulfonylbenzamido)benzal] 3- phenyl-Z-phenylimino-4-thiazolidone thus obtained was suspended in an alcoholic alkali (sodium hydroxide) solution, whereupon the desired, above-formulated sodium salt was obtained. The restuling solution was used directly for bathing of film or paper strips having thereon a developed and fixed photographic image.

The 5-(3-aminobenzal)-3-phenyl 2 phenylimino 4- thiazolidone used in the above example was prepared as follows:

A mixture of 6 g. (0.0167 mole) of 5-(3-nitrobenzal)- 3-phenyl-2-phenyliminoA-thiazolidone, 75 ml. of dioxane, 0.5 g. of sodium carbonate and 0.5 g. of Raney nickel catalyst was charged into a pressure bottle and shaken on a Parr hydrogenator under 42 pounds of hydrogen pressure at room temperature. After 3 hours the required volume of hydrogen had been absorbed and the bottle was removed from the machine and the solution filtered. The filtrate was evaporated in a vacuum, and the residue crystallized from 50 ml. of acetonitrile. The product obtained (5 g.) was light brown in color and showed a melting point of 280-282 C.

The 3 -phenyl-2-phenylimino-5-(3-nitrobenzal)-4-thiazolidone used above was prepared as follows:

A mixture of 13.4 g. (0.05 mole) of 3-phenyl-2- phenyliminoA-thiazolidone, 8.3 g. (0.05 mole) of m-nitrobenzaldehyde, 200 ml. of methyl alcohol and 4.3 ml. of piperidine was refluxed for 3 hours on a steam bath under a water-cooled condenser. The precipitate formed was filtered, washed with cold methyl alcohol, and dried. The bright yellow product was insoluble in most of the common organic solvents; it crystallized difficultly from boiling ethylene glycol. It had a melting point of 225- 227 C., and gave the following analytical results:

Calculated for 22 1sNaOaS Found Percent Carbon 6 omuq occurs:

Example .3-benzyl-Z-phenylimino-S-(o-sulfobenzal -4- thiazolidone (sodium salt) CeHsCHgN-C=O CeH5N=C C=CH SOaNa 70 g. of 3-benzyl-2-phenylimino-4-thiazolidone and 70 g. of sodium-benzaldehyde-Z-sulfonate (92% pure) in 700 cc. of glacial acetic acid were refluxed for 5-6 hours. After cooling to room temperature overnight, the crystals which had separated were filtered, washed with acetic acid and dried. :There were thus obtained 100 g., 85% of theory, of product. Addition of '10 g. of the o-sulfobenzaldehyde sodium salt to the filtrate and refluxing for 5 hours gave an additional 13 g. of pure material. Total yield 113 g., 96% of theory. The product was crystallized from 225 cc. of methanol to give a highly pure product.

The 3-benzyl-2-phenylimino-4-thiazolidone used in the above example was obtained as follows:

A mixture of 189 g. (0.79 mole) of 1 benzyl-3-ph'enylthiourea, M. P. 167-8 C., g. 1.0 mole) of chloroacetic acid and 95 g. (1.15 moles) of sodium acetate in 1000 cc. of ethanol was refluxed for 5-6 hours. About of the alcohol was removed under reduced pressure and 400 cc. of water was added. An oil separated which soon solidified. The aqueous layer was decanted, the residue washed thoroughly with water and taken up with benzene, treated with decolorizing carbon, and dried. An equal volume of ligroin was added and the solution chilled to give 149.5 g. of product as pure white crystals, M. P. 812 C. lhe mother liquors on spontaneously evaporating gave another 34 g. of product having a melting point of 79-81 C. Total yield 183 g., 83% theory.

The direction of cycl'ization was established by acid hydrolysis. Thus this product gave, on hydrolysis, an 87% yield of aniline, characterized as its acetyl derivative, M. P. ll3l14 C.

In a similar manner, 1,3-di(;8-phenylethyl)thiourea was reacted with chloroacetic acid to provide the thiazolidone which was obtained as a solid having melting point of 25-8 C. (3-f3-phenylethyl3-p-phenylethylimino-4- thiazolidone) Example 6.3-n-hexyl-Z-phenylimin05-(o-sulfobenzal)- 4-thiazolid0ne :(sodium salt) CaH NC=O CeH5N=C C=CH SOaNa 46 g. of 3-n-hexyl-2-phenylimino-4-thiazolidone and 36 g. of o-sulfobenzaldehyde sodium salt in '150 cc. of acetic acid were refluxed for 7 hours. On cooling, the reaction mixture set to a solid crystalline mass which was filtered and washed with acetic acid. Yield, 71 g.

Example 7.3-benzyl-2-benzylimin0-5-(o-sulfobenzal)-4- thiazolidone (sodium salt) CaHsCH2N-C=O CuH5OH -N=O C=CH- SOsNa A mixture of 74 g. of 3-benzyl-2-benzylimino-4-thiazolidone, 60 g. of o-sulfobenzaldehyde, 20 g. of sodium acetate and 500 ml. of acetic acid was refluxed for 5 hours. Complete solution ensued. The acetic acid was evaporated under reduced pressure, while the reaction mixture was alternately allowed to cool and the precipitate filtered off. After all liquids had been removed, the residue and precipitates were recrystallized from water. Pure white crystals weighing g. were obtained.

The 3-benzyl-2-benzylimino-4-thiazolidone used above was prepared as follows:

A mixture of 52 g. of 1,3-dibenzylthiourea, 24 g. of chloroacetic acid, 24 g. of sodium acetate, and 200 ml. of ethanol was refluxed for 5 hours. The alcohol was then removed in vacuo and the residue treated with 300 ml. of water to remove excess chloroacetic acid, sodium acetate, and sodium chloride. The insoluble portion was recrystallized from alcohol to yield 56 g. of product, M. P. 84-86 C.

Instead of using the compounds containing an acid group (e. g. carboxyl or suite) in the form of their alkali metal salts, they can be employed in the form of their amine addition salts (e. g. ethyl amine, diethylamine, amylamine, lauryl amine, triethanolamine, etc.). The alkali metal (e. g. sodium, etc.) salt can be dissolved in water, advantageously with the aid of ethyl methyl ketone, and the amine, :e. g. triethanolamine, added. The desired salt then separates on chilling the solution and it can easily be redissolved in warm water.

The 4-flhiazolidones represented by Formula II above can be prepared as shown in the above examples, i. e. by condensing a thiourea together with chloroacetic acid in the presence of sodium acetate and an inert diluent.

8 done was dissolved in 2 cc. of tri-o-cresyl phosphate. This solution was added to 20 cc. 10% gelatin (aqueous) and 4 cc. of 5% aqueous ethanol, and the mixture homogenized in a colloid mill. The resultant dispersion In a manner similar to that illustrated in the above 5 heuctia ei onbag lp q pl gl P film pp o examples the following 4-th1azol1dones were prepared, eflgcuve y a sot e U ct m anon the results being given in Tables I and II. The extinction Example 9 coetficient, e, is given for some of the compounds. 1.0 g. of 3-benzyl-2-phenyhm1no-5-(2-sulfobenzal)-4- TABLE I I I R!!! C=CHR,,I, s RI! Absorp- RI RI! RIII RI! A c max. (mu) H H as osNa H 334 19, 500 H H 3-SO Na -OCH; 355 28,000 et-05H 4-t-C5Hu 2-SO3N8 H 328 16, 500 -C a 4-CH3 Z-SOaNa H 330 20,000 4-CQH5 4-CH5 2-SO3Na H 328 19, 200 2-CH3 2-CH3 2-SO Na H 330 11, 600 4-O2H5 4-0 02H; 3-SOaNa -OCH: 352 25,000 4- zH4OH 4-01H40H B-SOzNa -OCH3 355 .000

TABLE II RN ?=O R'" RoN=1\ =CH 1 Absorp- R R0 R' 3" tion A 1 max. (mu) G2H5 -GH5 3-SO3N8 OOH3 34s 25, 200 -0H.0,H5 GH2CaH5 2-SO3Na H 330 20, 400 H 5H5 2-SO3N3 H 338 22,000 -G2H5 -OH5 Z-SOsNB H 334 15, 200 (CzHsOhCHCHa- -0.H5 2-SO Na H 334 17, 000 CHzCaH5 -CHzCgH5 3-SO3N3 0 CH; 348 26, 600 CH2C6H5 o HzCuHs 3-SO3Na H 332 24, 000 CH2CH2C5H5 OHzCH C H 2-SO3Na H 330 27. 000 -CaH13('n) sH13(1t) 2-SOsNa H 330 12,000 -OH(OH3) CH OH(GH3) C Hs 2-SO Na H 330 16, 000 CH(OH3) C6115 CH(CH3) 08H; 3-SOsNa --0 OH: 350 20, 000

C2 5 CzH5 00H H 329 23.20 --OH2O5H5 --C6H5 2-SO3Na H 330 19,000 C16H33(n) C H5 H H 329 24, 800 a 1a(n) C@H5 H H 330 24, 800 6H11(0y 01 C6H5 H H 330 27, 000 C4Hfl o6H5 H H 330 24, 600

l N caled. 6.1, found 6.0; S calcd. 13.9, found 14.1. 1 M P. 138-9 0. from OH3CN and water.

The following examples will serve to illustrate the application of the compounds 'of Formula I to photographic elements.

Example 8 1.0 g. of 5-benzal-3-benzyl 2 phenylimino-4-thiazolithiaz'olid'one sodium salt was dissolved by warming in 20 cc. of water. After mixing with 20 cc. of 10% gelatin the mixture was coated as before on opaque and transparent film supports.

Co'atings prepared as described in Examples 8 and 9 above showed no loss in density on undergoing normal photographic processing and were unchanged after one weeks exposure on an east window.

The term an imino group as employed herein includes the simple imino group (HN=) and its substituted derivatives (R2N=, wherein R2 represents an aryl or aralkyl group, such 'as those listed above, for example).

The solutions containing the ultraviolet absorbing compounds of my invention can also be used in bathing solutions for after treatments in photographic processes, glazes, etc.

The thi'oureas required for the production of the thiazolidones of Formula II wherein Q is Rz-N= can be obtained according to the method of Hofmann (Ber.," vol. 1, page 27), i. e. by condensing ammonia or an amine having the formula R-NHz together with an isowherein R represents a hydrocarbon aralkyl group containing from 7 to 8 carbon atoms, and M represents an alkali metal atom.

2. The compound represented by the following formula:

CeHs-N= 3 011- OsNa 3. A compound selected from those represented by the following general formula:

RN--O=O Rr-N= =CH-R1 wherein R represents a member selected from the group consisting of a hydrogen atom, a hydrocarbon alkyl group containing from 1 to 16 carbon atoms, fl-hydroxyethyl, fl-sulfoethyl, fi-diethoxyethyl, cyclopentyl, cyclohexyl, a hydrocarbon aralkyl group containing from 7 to 8 carbon atoms, a monocyclic hydrocarbon aryl group of the benzene series containing from 6 to 11 carbon atoms, fl-hydroxyethylphenyl, methoxyphenyl, ethoxyphenyl, chlorophenyl, hydroxyphenyl, sulfophenyl, alkali metal salts of sulfophenyl, methoxysulfophenyl, alkali metal salts of methoxysulfophenyl, 2,4-dicarboxymethoxyphenyl, alkali metal of salts of 2,4-dicarboxymethoxyphenyl, carboxyphenyl, alkali metal salts of carboxyphenyl, sulfobenzamidophenyl, alkali metal salts of sulfobenzamidophenyl, carbobutoxyphenyl, and diamylphenoxyacetoxyphenyl, R1 represents a member selected from the group consisting of sulfophenyl, alkali metal salts of sulfophenyl, 2,4-dicarboxymethoxyphenyl, alkali metal salts of 2,4dicarboxymethoxyphenyl, methoxysulfophenyl, alkali metal salts of methoxysulfophenyl, sulfobenzamidophenyl, alkali metal salts of sulfobenzamidophenyl, carboxyphenyl, and alkali metal salts of carboxyphenyl, and R2 represents a member selected from the group consisting of a hydrocarbon alkyl group containing from 2 to 6 carbon atoms, a monocyclic hydrocarbon aryl group of the benzene series containing from 6 to 11 carbon atoms, p-hydroxyethylphenyl, ethoxyphenyl, chlorophenyl, and a hydrocarbon aralkyl group containing from 7 to 8 carbon atoms.

No references cited. 

3. A COMPOUND SELECTED FROM THOSE REPRESENTED BY THE FOLLOWING GENERAL FORMULA: 